Method for fast circuit switched service enabling handover from packet-switched only networks

Abstract

Quick and efficient handover of a user equipment (UE) from a Wideband Code-Division Multiple Access (WCDMA) packet switched only network to a Circuit Switched enabled (CSe) network is provided by certain embodiments. Parallelization of the Radio Access Network (RAN) processes and the User Equipment (UE) processes can help to reduce delay in such handovers.

What is claimed is: 
     
       1. A method, comprising:
 initiating, by a network node of a packet switched network responsive to receiving a request for a circuit switched connection, establishment of the circuit switched connection, wherein the circuit switched connection regards a user equipment that is associated with the packet switched network, wherein the request comprises a plurality of parameters relating to the establishment of the circuit switched connection, wherein at least one of the plurality of parameters are associated with at least one radio resource control transparent container information element, and wherein the at least one radio resource control transparent container information element comprises one or more of at least one non access stratum protocol data unit, at least one location area identity, and at least one service area identifier; and 
 transferring, by the network node of the packet switched network, information regarding the initiating of the establishment of the circuit switched connection from the packet switched network to a circuit switched enabled network comprising at least one radio resource control transparent container information element, 
 wherein the user equipment already has a radio resource control connection setup and an active packet switched connection when the request for the circuit switched connection is made. 
 
     
     
       2. The method of  claim 1 , wherein the initiating the circuit switched connection comprises the circuit switched connection being requested from the user equipment. 
     
     
       3. The method of  claim 1 , wherein the request comprises an initial direct transfer protocol data unit with a non-access stratum message. 
     
     
       4. An apparatus, comprising:
 at least one processor; and 
 at least one memory including computer program code, 
 wherein the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: 
 initiate, responsive to receiving a request for a circuit switched connection, establishment of the circuit switched connection, wherein the circuit switched connection regards a user equipment that is associated with the packet switched network, wherein the request comprises a plurality of parameters relating to the establishment of the circuit switched connection, wherein at least one of the plurality of parameters are associated with at least one radio resource control transparent container information element, and wherein the at least one radio resource control transparent container information element comprises one or more of at least one non access stratum protocol data unit, at least one location area identity, and at least one service area identifier; and 
 transfer information regarding the initiating of the establishment of the circuit switched connection from the packet switched network to a circuit switched enabled network comprising at least one radio resource control transparent container information element, 
 wherein the user equipment already has a radio resource control connection setup and an active packet switched connection when the request for the circuit switched connection is made. 
 
     
     
       5. The apparatus of  claim 4 , wherein the initiating the circuit switched connection comprises the circuit switched connection being requested from the user equipment. 
     
     
       6. The apparatus of  claim 4 , wherein the request comprises an initial direct transfer protocol data unit with a non-access stratum message. 
     
     
       7. A computer program, embodied on a non-transitory computer readable medium, the computer program, when executed by a processor, causes the processor to:
 initiate, responsive to receiving a request for a circuit switched connection, establishment of the circuit switched connection, wherein the circuit switched connection regards a user equipment that is associated with the packet switched network, wherein the request comprises a plurality of parameters relating to the establishment of the circuit switched connection, wherein at least one of the plurality of parameters are associated with at least one radio resource control transparent container information element, and wherein the at least one radio resource control transparent container information element comprises one or more of at least one non access stratum protocol data unit, at least one location area identity, and at least one service area identifier; and 
 transfer information regarding the initiating of the establishment of the circuit switched connection from the packet switched network to a circuit switched enabled network comprising at least one radio resource control transparent container information element comprising at least one radio resource control transparent container information element, 
 wherein the user equipment already has a radio resource control connection setup and an active packet switched connection when the request for the circuit switched connection is made. 
 
     
     
       8. The computer program of  claim 7 , wherein the initiating the circuit switched connection comprises the circuit switched connection being requested from the user equipment. 
     
     
       9. The computer program of  claim 7 , wherein the request comprises an initial direct transfer protocol data unit with a non-access stratum message.